Principal axis may refer to:
- Principal axis (mechanics)
- Aircraft principal axes
- Principal axis theorem
- Principal axes of a Matrix
- Principal axis (crystallography)
- Optical axis
Famous quotes containing the words principal and/or axis:
“The principal difference between love and hate is that love is a irradiation, and hate is a concentration. Love makes everything lovely; hate concentrates itself on the object of its hatred.”
—Sydney J. Harris (b. 1917)
“A book is not an autonomous entity: it is a relation, an axis of innumerable relations. One literature differs from another, be it earlier or later, not because of the texts but because of the way they are read: if I could read any page from the present time—this one, for instance—as it will be read in the year 2000, I would know what the literature of the year 2000 would be like.”
—Jorge Luis Borges (1899–1986)